Short fill detector and rejector



, Dec. 10, 1968 RQK. HENNIG SHORT FILL DETECTOR AND REJECT OR 2 Sheets-Sheet 1 Filed Nov. 25 1966 INVENTOR ATTORNEY Dec. 10, 1968 K; 3,415,369

SHORT FILL DETECTOR AND REJECTOR Filed Nov. 25, 1966 2 Sheets-Sheet 2 ATTORNEY United States Patent 3,415,369 SHORT FILL DETECTOR AND REJECTOR Roy K. Hennig, Cincinnati, Ohio, assignor to Richard- Merrell Inc., New York, N.Y., a corporation of Delaware Filed Nov. 25, 1966, Ser. No. 596,924 2 (Jlaims. (Cl. 209-88) ABSTRACT OF THE DISCLOSURE A reciprocating sensing arm detects presence or absence of articles in a receptacle. The arm reciprocates in timed relation to detect only the bottom position of each receptacle without contacting the other portions of said receptacle. The receptacles are then sorted according to the results of this test.

This invention relates to a method and apparatus for detecting a shortage in the number of articles in package strip compartments as they leave the packaging machine. The invention also relates to a method and apparatus for segregating the package strip compartments having a short fill from those which contain the proper number of articles.

Apparatus of this invention is employed as an attachment or in conjunction with machines for making and filling packages from two layers of packaging material, for example, strips of cellophane, metal foil, paper and the like wherein two layers of packaging material are fed into juxtaposition and sealed together to form a bag having an upwardly facing open end after which a series of articles are inserted into the bag and then the said open end of the bag is closed, a plurality of such bags or packages being made in succession from continuous strips of packaging material. In the method of operation of such machines, the strips of material are moved through the machine between cooperative sealing dies with a step by step motion, and at the end of each step of movement, the dies press the strips together simultaneously along their longitudinal margins and transversely to form a rectangular bag-like container or compartment having an open end. The two sides and bottom of the rectangular compartment formed by the longitudinal and transverse seals, respectively, and the open end or mouth facing upwardly being formed between the unsealed portions of the strips at the upper ends of said longitudinal sealed zones. At the same time, the open end of the next preceding baglike container is sealed by again sealing the strips transversely between the upper ends of said longitudinal sealed zones. With this method, the last mentioned end of a given package is sealed at a different time and independently of the sealing of the strips together to form the other three sides of the package. In the interval between the steps of movement and after the partial formation of each package, the articles to be packaged are deposited, through gravity feed, by a filling mechanism into the mouth of the preceding bag-like receptacle.

The articles are forced in succession through the mouth of the open bag-like receptacle, with either one or more articles in each receptacle, and are aligned therein in a single row substantially parallel to the longitudinal axis of the package strip. As mentioned hereinbefore, the packages are produced and filled by step-wise movement of the continuous packaging material and the operations, such as the filling of the compartment, are in timed relationship to the step-wise movement of the packaging material. Such timing is by gearing off of the main shaft of the machine or it can be through cams mounted on the main or an auxiliary shaft which open or close elec- 3,415,369 Patented Dec. 10, 1968 trical contacts as they revolve past predetermined points. In general, such machines for making and filling such packages with which this invention is employed are of the general type shown or described in US. Patents 2,601,920 which issued on July 1, 1952; and 2,512,216, which issued on June 20, 1950.

In packaging a plurality of articles in the compartments by the above-described machines and method, occasionally the compartment contains less than the intended number of articles due to a failure of the filling mechanism. In such cases I have noticed that when a shortage occurs it results in the failure of the first article placed into the package from being placed into the bottom (as filling occurs) position. Briefly, therefore, my invention comprises apparatus and method for sensing whether or not the first position (or bottom) in the compartment is occupied by an article and rejecting those compartments which do not have an article in such position. It can be seen that this is an eificient expedient since it is not necessary to check the entire package for short fill, but only the bottom portion thereof which is normally occupied by the first article placed into the receptacle in the filling operation.

It is a primary object of this invention to provide simple and etficient apparatus and method for detecting and rejecting sealed receptacles of a package strip, normally containing more than one article, when the receptacle contains less than the proper number of articles. Other objects, advantages and results of the invention will be brought out by the following description in conjunction with the accompanying drawings, wherein identical numerals refer to identical parts and in which:

FIG. 1 is a simplified perspective view of the short fill detector and rejector apparatus embodying the invention, with portions broken away;

FIG. 2 is a front elevational view of another em bodiment of the short fill detector and rejector apparatus embodying the invention, with portions broken away.

Referring now to the drawings, and specifically to FIG. 1, a package strip 1.0, after filling and complete sealing about its periphery 14 to form rectangular receptacle 12 containing a longitudinal row of articles 16 having substantially the same shape and size are moved step by step by frictional foil advancing wheels 18 mounted on shafts 20 and 22. In FIG. 1 there is shown a package strip having two receptacles in side by side relationship. However, for the sake of simplicity the invention will be further described for a single longitudinal series of receptacles 12. On one side of package strip 12, in the vicinity or adjacent to rollers 18 is a reciprocal sensing arm 24 which moves toward or away from the position normally occupied by the first or bottom anticle in the receptacle. The reciprocation of sensing arm 24 is in timed relationship to the step by step, intermittent, movement of the package strip. When the bottom position of the receptacle is occupied, the sensing arm is obstructed from making its complete distance of travel. When the bottom position of the receptacle is empty, the sensing arm 24 travels a longer distance which can be about equal to the thickness of the article 16. In the latter case, means are activated or put in motion so as to separate or reject the short filled receptacle from those with normal or proper fill. In the scheme depicted in FIG. 1, both of the side by side receptacles would be separated out in the case of a short fill; also when a plurality of side by side receptacles are being made and filled it is desirable to have a sensing arm for the bottom position of each of the longitudinal rows, e.g., in the case of FIG. 1 there would normally be two sensing arms. The sensing arm is mounted and reciprocated in timed relationship by apparatus and methods well known in the art. In this case such apparatus and method are simply designated by the box 26 which has a linkage or connection 27 to a timing and memory device 28. Suitable means for mounting the sensing arm are shown in FIG. 2. The timed relationship of the sensing arm 24 can also be effected by conventional means such as appropriate gearing and springs wherein reciprocation is synchronized with the shaft 20 or a main or auxiliary shaft of the packaging machine. Alternatively, timed reciprocation of the sensing arm to contact or sense only at the bottom or first position can also be effected by other conventional means well known in the :art such as cams mounted on the packaging machine main or auxiliary shaiit and electrically connected to counters and other timing devices so as to be synchronized with the step by step movement of the package strip. In any event, reciprocation of the sensing arm is operatively timed so that it moves toward and contacts the bottom position of each receptacle of the package strip while omitting contact of the other positions and articles normally contained in the receptacle.

After the sensing arm has performed its function, the receptacle is moved downwardly in step-wise timed relationship so that the package strip is in position for severing transversely by cutters 32. This is a conventional step in such packaging and filling machines. The receptacle moves downwardly and if it is properly filled the deflector plate 40 is aligned with slide 42 and the receptacle assumes the position shown at A. Each receptacle 12 is severed from the package strip or chain of receptacles 19 by the cutters 32. The timing of the opening and closing movement of the deflector plate 40 is synchronized with the cutter. As shown in FIG. 1, the deflector is moved downwardly, in the case of a short filled package, to leave an opening between slide 42 prior to severing of the receptacle from the package strip. Actuation of the deflector is by action of a motor or cam 36 which receives signals from the timing and memory device 28 which in turn can be synchronized with the shaft 20 or the main shaft of the machine through linkage or connection 30.

The embodiment in FIG. 2 shows details for the mounting of the sensing arm 24 and different power means for retracting the deflector 40 to reject short filled packages. A support rod 46 reciprocal toward and away from package strip 12 carries a support 48 for part of the sensor arm assembly through plate 50 and clamp 51. Mounted on support 48 are leaf springs 52-56 connected with plate 58 on which the sensing arm 24 is mounted. Due to the movement of support 46, the sensing arm reciprocates to contact the first or bottom position in each receptacle .12. A sensor assembly comprising sensor shield 60, spacer 62, sensor box 64, gasket 66 and back plate 68 is mounted on sensor box holder 70 which in turn is mounted on sensor box support 72. A shield 74, which supports part 72, protects the cutter 32. Also attached to shield 74 is arm 75 which carries the adjustable chute support 76 which in turn carries air cylinder 80 through support 7 8.

In FIG. 2 the sensor arm 24 reciprocates in timed relation to the movement of strip to contact the bottom position of the receptacle 12 while by-passing the positions normally occupied by the other articles in the receptacle. Each receptacle is then severed from the package strip and falls by gravity on slide deflector 40 and then moves by gravity to slide 42. However, if the sensor arm does not strike an article in the bottom position of the receptacle it moves by a longer distance than normally and plate 58 moves close to the proximity sensor (not shown) which is protected by shield 60. This gives a signal which is eventually transmitted to the mechanism controlling the air cylinder so that the slide 40 is pulled away from slide 42 and the short filled receptacle, after cutting, falls into bin 44. The actuation of the air cylinder is in timed relationship with the movement of the package strip and since the short filled receptacle is not in position to be rejected at the time the sensor arm determines the shortage, means for delaying actuation of the air cylinder are employed. Such delay and timing means are conventional and well known in the art.

What is claimed is:

1. In a packaging machine for making and filling a package strip as a chain of substantially rectangular receptacles with articles of substantially the same size and shape, wherein each receptacle is filled by depositing a plurality of articles in series relationship by gravity into each partly formed receptacle of the package strip through the top of each receptacle, the first of said articles occupying a position in the bottom of the receptacle, wherein the machine has means for sealing and transversely cutting the receptacles from the package strip, the filling, sealing and cutting performed in timed relationship with the movement of the package strip through the machine, the improvement which comprises a reciprocable sensor arm, means for advancing said arm to contact only the bottom position of each receptacle and to retract said arm therefrom without contacting the other positions of said receptacle, and means, in timed relationship with the sensor arm, for segregating the packages in which the bottom position is not occupied, from the receptacles in which the bottom position is occupied.

2. In a method for detecting and rejecting receptacles having a short fill in a packaging machine for making and filling a package strip as a chain of rectangular receptacles with articles of substantially the same size and shape, wherein each receptacle is filled by depositing a plurality of articles in series relationship by gravity into each partly formed receptacle of the package strip through the top of the receptacle, the first of said articles occupying a position in the bottom of the receptacle, wherein the tops of the receptacles are subsequently sealed and then the receptacles are cut from the package strip, the filling, sealing and cutting performed in timed relationship with the movement of the package strip through the machine, the improvement which comprises feeling and detecting the absence of an article in the bottom position of each receptacle by the movement of a sensing arm while by-passing the positions in each receptacle normally occupied by the remaining articles, passing a signal to segregate the short filled receptacle after it is cut from the package strip, said signal activated by the length of travel of the sensing arm.

References Cited UNITED STATES PATENTS 3,117,441 1/ 1964 Zimmerman 209-73 X 3,319,784 5/1967 Granger 209-88 X 3,359,702 12/ 1967- Beert -a 20988 X M. HENSON WOOD, 111., Primary Examiner.

R. A. SCHACHER, Assistant Examiner.

U.S. Cl. X.R. 5353 Patent No. 3,415,369 December 10, 1968 Roy K. Hennig It is certified that error patent and that said Letters P shown below:

appears in the above identified atent are hereby corrected as In the heading to the printed specification, lines 3 and 4, "Richard- Merrell lnc.,"

should read Rlchardson-Merrell Inc.,

Signed and sealed this 10th day of March 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr. E. SCHUYLER,

Attesting Officer Commissioner of Patents 

